Is Interval Training the Best Prescription for Belly Fat?

Is Interval Training the Best Prescription for Belly Fat?

(Last Updated On: June 9, 2019)

Belly fat is more than an aesthetic nuisance that makes it harder to get into your favorite pair of jeans. It’s a marker of future chronic disease risk. That’s because belly fat, particularly the deep kind known as visceral fat, is correlated with a higher risk of type 2 diabetes, cardiovascular disease, and some types of cancer. Deep belly fat is also associated with a higher risk of non-alcoholic fatty liver disease, a growing epidemic fueled by obesity and excess tummy fat.

Unfortunately, many people fight a battle with belly fat after the age of 50 as hormone levels shift. Intuitively, people want to believe that doing hundreds of crunches will melt away the belly fat. But sit-ups don’t burn enough calories to cause significant fat loss and you can’t spot reduce fat. Crunches and sit-ups only strengthen the muscles underneath the fat. Could interval training be the ticket to less belly fat and healthier body composition?

As mentioned, belly fat accumulates with age. So, the average 70-year-old person will have more of it than someone in their 20s or 30s. Yet, even older people may be able to reduce belly fat through the type of exercise we know as interval training, also known as HIIT. As you know, interval workouts alternate between periods of high-intensity exercise followed by short rest periods to allow partial recovery. Then, another active interval follows, and it’s back-and-forth until the workout ends. Interval workouts are more time expedient than steady-state cardio, and research suggests that vigorous exercise may have more health and fitness benefits. Vigorous interval training is the approach researchers used to explore the impact of interval training on belly fat in people over the age of 70 with belly fat.

Trim Belly Fat with Interval Training

For the study, 70-year-old men and women took part in a 10-week high-intensity interval workout using body weight exercises. The program consisted of short, supervised training sessions performed in a group setting with little equipment. The sessions took place three times per week for 10 weeks. The ratio of active to rest intervals was 40 seconds active exercise to 20 seconds of rest. The participants started out with shorter workouts but gradually worked their way up to sweat sessions that totaled 36 minutes. Thirty-six people made up the exercise group, and another 36 were in the control group and did no exercise. Both groups, however, received dietary and health advice for staying healthy and controlling body fat.

The results? In the study, the participants who took part in the program gained lean body mass and lost body fat. In fact, loss of body fat was three times greater in the group that did the HIIT training relative to the control group. However, loss of visceral belly fat was significant only in men. Still, the women lost total body fat, gained muscle, and improved their body composition. It’s not clear why the men lost more visceral belly fat than the women. However, previous research finds exercise, in general, helps with visceral fat loss. One meta-analysis showed exercise alone, in the absence of weight loss, was linked with a 6.1% loss of visceral fat. This analysis found that both diet and exercise can lead to loss of visceral fat, but exercise is more powerful for loss of visceral fat relative to diet while diet is more beneficial for total weight loss.

High-intensity interval training may be of benefit for fat loss in older individuals, but is it the only way to trim the tummy? Due to its intense nature, HIIT training offers some advantages over moderate-intensity exercise. It creates more of an afterburn that forces the body to work harder to recover and stimulates a greater release of fat-burning hormones. But any form of exercise offers some benefit. Researchers at Louisiana State University found those who walked at least 30 minutes three times weekly experienced a 20% shrinkage of tummy fat cells. Exercise, in general, especially when combined with good nutrition, can take a bit out of belly fat.

How Do You Know if You Have Too Much Belly Fat?

By now, you’re probably wondering whether your waistline could use some work. How do you stand in terms of belly fat? A tape measure can tell you a lot. A healthy woman should have a waist circumference no greater than 30 inches and even less is better from a health standpoint. In fact, an NIH study found that women with a waist size greater than 28 inches had double the odds of dying of cardiovascular disease relative to women with a slimmer waistline. So, keep tabs on your waist size by keeping a tape measure handy. Researchers believe that waist size trumps weight as a predictor of health risks. Unfortunately, many doctors don’t measure and follow waist size in patients over time–but they should! It’s also important for us to follow our own waist measurements at home and track them over time.

Nutrition Matters Too

Belly fat, particularly visceral fat, is a major health risk, and it’s harder to control it as we age. The best approach is to use a combination exercise and a nutritional approach. In terms of nutrition, eliminate the junk, especially sugar-sweetened beverages! A study published in the journal Circulation found that drinking one or more sugar-sweetened drinks daily was linked with a 27% greater increase in visceral fat over a 6-year period. Eliminate carbs and ultra-processed foods too. Your best bet is fiber-rich carbs, lean proteins, and healthy fat sources, like the monounsaturated fats in olive oil, avocados, and nuts.

The Bottom Line

Exercise and good nutrition – they both matter in terms of belly fat and for reducing health risks. So, don’t focus on one or the other but both. Your body will thank you for the care you’re giving it!